Electronic transport in Si and Au monoatomic chains considering strongly correlation effect, a first principle study

We have investigated structure and electronic properties of Au and Si liner chains using the firstprinciples plane wave pseudopotential method. The transport properties and conductance of these two liner chains are studied using Landauer approaches based on density functional theory (DFT). We obtain density of states and band gap using Kohn-Sham and Wannier functions as well as quantum conductivity and current for Au and Si liner chains. We study the effect of Hubbard U on quantum conductivity and current for Au liner chain within DFT+U for strongly correlated systems. We compare the source of the states around Fermi level of these systems that have important role in conductivity. We present I-V characteristics of the Si and Au liner chain. Results show Ohmic behavior of current flow in the liner chains in terms of applied bias voltage. We show that Hubbard U correction removes the unphysical contribution of d electrons to the conductance of Au liner chain, resulting in a single transmission channel and a more realistic conductance of 1G0 that is in good agreement with experimental results. Our calculations reveal that monatomic chains of Si and Au are metallic therefore they can be used as connectors between nanoelectronic devices.